Coated paper is developed with screen printing. Since the surface unevenness composed of uncoated paper fibers is much larger than the diameter of the dots, some dots are just in the gap between the fibers and cannot transfer the ink. onto the paper, making the image pixels unreproducible in this area. After the paper is coated with the slurry and then calendered, the particles on the surface of the paper are smaller than the diameter of the dots, and the ink acceptability of the slurry is also better than that of cellulose fibers, so the dots can be reproduced correctly. Clearly, the printing performance of the coated coated paper is better than that of the uncoated offset paper.
Coated paper base paper adopts high-quality roll newsprint or offset printing paper, and high-grade coated paper adopts special base paper. The surface coating adheres firmly to the base paper. The paper surface is super calendered again, the coating is firm, no bubbles, no streaks, strong gloss and high smoothness. The smoothness of coated paper is generally above 600s, which is more than 10 times higher than that of offset paper. In this way, the coated paper can be in close contact with the printing plate, and the dots can be printed clearly.
The pH value of the coated paper is around 7, which has no adverse effect on the lithographic wetting solution and has no adverse effect on the drying process of the ink. The ink adheres quickly and dries quickly on the coated paper. After drying, it can also bring out the luster. The dot reproducibility is good, the ink layer is thin, the image is clear, and the dot is smooth. The dimensional stability of coated paper is also better than that of offset paper. Printing on coated paper can meet the requirements of overprinting accuracy. The coated paper also has high tensile strength and surface strength, which is high enough to resist the large tensile forces of the more viscous ink films used.
Due to the above points, coated paper is often used to print high-grade prints. If you want to learn more, you can click here: coated paper hardcover notebook.